So I've created this creature I'm calling the Shod, short for shadow of death. This creature lives in space and looks like a massive, black cloud. Inside the Shod, particles move at immense speeds, constant levels of radiation in all parts of the EM spectrum, electric currents, magnetic fields, and heavy gravity. The core of the Shod is super dense, and functions as the brain. They rarely move their entire bodies, but prefer to manipulate their bodies into thin, easily manipulated tendrils. They use planets to reproduce and incubate their young, and are capable of wiping out star systems easily. Shod consume stars and planets for fuel, and are capable of manipulating their bodies at will.
However, since the body of this creature is mostly in a gaseous or plasma state, it is constantly in danger from things like solar winds and other types of space weather that could disperse at least part of its body. So what I'm looking for is some type of space phenomenon that would not only threaten a creature like this, but would also ensure that it is unable to go wherever it wants. Specifically, I want to keep it away from a certain part of the galaxy, so that space travel is much safer there, but far more dangerous past a certain point.
I would prefer something natural, as opposed to artificial alien or human made, and as close to reality as possible.